Query :limit

[mokr]

Add support for query :limit (and related :offset)

Based on response on Slack and googled suggestions for Datomic, there seems to be at least two alternatives for implementation:

1. In the map form of q. Like {:query '[:find ... :where ...] ... :limit 20 offset: 40}
2. In the map form of the query itself like {:find ... :where ... :limit 20 offset: 40}.

Alternative 1 reflects the suggestion in this response in Datomic forum (documented here). One benefit I see for this approach is that it allows you to keep queries in vector form (possibly in a separate file) and only wrap them up in a map when limiting is needed.

If it fits and is not already implemented, support for :timeout could be added as well.

[huahaiy]

Putting :limit etc. in the vector form works too. A vector actually has more freedom than a map, as it does not have to be an even number of items.

[huahaiy]

Seems to be related to #117

[huahaiy]

:timeout is already supported.